Pioglitazone and a salt thereof give a bitter taste for those having a normal sense of taste.
As a preparation masking the unpleasant taste, particularly an unpleasant taste of a pharmaceutical ingredient having a bitter taste, the following preparations have been reported.
A solid preparation containing 1) a basic medicinal component having an unpleasant taste, 2) a saccharide, 3) a polyanionic polymer, 4) a corrigent and 5) carboxymethylcellulose (see patent reference 1); and
an ecabet sodium-containing oral preparation containing ecabet sodium and alkali chloride as a bitter taste masking agent (see patent reference 2).    Patent reference 1: WO 02/30400    Patent reference 2: JP-A-H7-165572